System of distribution.



I.` E. BOGEN & L C. NHHOLS,

SYSTEM 0F DIS`=`RIELVI`0NK M'PLlcATloN FILED MAY :3 mo.

l 1 50,4 1 6. lzmmed Aug'. l?? MLS.

f5 vwemxom y WN? gpm/Ly UNITED STATES PATENT ormoni LOUIS E. BOGEN ANDLOUS C. NICHOLS, F MILWAUKEE, WISCONSIN, ASSIGNORS, ,BY MESNEASSIGNMENTS, T ALLIS-CHALMERS IMI.AN-lll'FAG'.I`U`.!3II1\T(=|Y COMPANY,A .COR-

PORATIOAN. OF DELAWARE.

SYSTEM OF DISTRIBUTION.

Application med may I3, 1910. senal No. 561,207.

c To allwhom 'it may conc-cm:

-clear, and exact specification.

`Our'invention relates to systems of dis.-

`tribution, and particularly to the operation of a plurality`A of rotaryconverters connected in parallel both on the D.y C. and the A. Cfends. b

When two or more rotary converters 'are .fconnected in parallel on boththe D. C. and

A. C. ends, it is desirable that the several converters divide the loadin proportion to their respective capacities'. For a number of causesthe load at different times might become otherwise divided, and theconverters would tend to' hunt. By reason of this hunting there mightarise a most undesirable surging o'f current between the machines. l b c1t is the object of our invention to maintain the proportionate divisionof the current, and to prevent such hunting and. surging.

N In A'carrying out our invention there is provided a device which is soconnected to.

' the yrotary converters that it offers ay large impedance to surges ofcurrent between the machines while oifering little or no impedance tothe How of current between the A. C. and D, C. circuits. This deviceconsists of transformer windings connected in the parallel circuitsbetween the A. C. ends of the several converters and the A. C. line,

.andarranged in inductive inter-relation so that they react amongthemselves to offer small impedance to the proportionate flow of.current through the several converters between the A. C. and D. C.lines but to oiiera large impedance to the flow of current from onemachine to another. The inductive relation between the windingsconnected to the several converters is such that `in case theicurrentstaken lby the different machines tend to varydisproportionately thecurrents traversing the several windings .will so react upony oneanother that the proper yproportion. is immediately restored.I

The various novel features of our inven- Specication of Lettersira/cent.

the A. C. and D. C. circuits.

patented Aug. 17, 1915.

tionwill be apparent fronrthe description and drawing and will beparticularly pointed out in the claims. l

The. single igure of the drawing shows diagrammatically one embodimentof our lbe' excitedv in` any suitable manner.v The D. C. ends of theconverters are connected directly to the D. C. circuit 12B- 14, and theA. C, ends of the machines may be either conductiv'ely or inductivelyconnected to the A. C. circuit 10-11-12. As illustrated, they areinductively connected through the transformer 18. The three leads 19,20, and 21 from the A. C. end of the converter 15 extend to coils 22,23, and 24 respectively, while the leads 25, 26, and 27 from the A. C.end of the converter 16 extend to coils 28, 29, and 30 respective-ly.The ends 0f the coils 22 and 28, 23 and 29, and 24 and 30lremote fromthe'converters are connected together respectively, and arealsoconnected, through the transformer 18 if it is used, to the A. C.circuitl101112. The sets of connected coils, as 22 and 28, form thewindings on the same legs of a three-phase transformer 31, asillustrated, but are Oppositively disposed on such legs for currentsbetween The turns of the two sets of windings of this transformer areproportioned inversely to the capacities of the converters to which theyare respec tively connected.

As the result of the arrangement above described, the transformer 31produces little or no effect upon the flow of current between the A. C.and D. C. circuits as long as such current is divided in the properproportion between the converters 15 and 16, for` the ampere turns ofthewindings 22, 23, and 24 are equal and opposed to the ampere turns Theserotary con- 'force is induced in the windingsl having Vao the smallernumber of ampere turns tending 'to raise the current in -such windingand thus to restore the equality between the ampere turns of the twosets of coils and the proportionate division oi' the current between.the converters. lVhen because of a disproportionate division of thecurrent between the converters there is a tendency for the current tosurge from one machine to another, such surging current traverses thetwo sets of transformer windings in series and the latter assist eachother and oder a large impedance to suchflow of current. This tends toprevent such surging current and almost completely overcomes anytendency to hunt. 4

For the purposes of this description one of the simplest cases has beentaken, but the invention is not limited to the specific case described.It may be used when the plurality of rotary converters numbers otherthan two when properly grouped, and when they are other than three-phaseconverters. These modifications and many others come within the broadscope of our invention and are intended to be covered in the followingclaims.

' What we claim as new is:

l. In combination, a source of polyphase alternating current, a directcurrent circuit, a plurality of rotary converters connected in parallelto said direct current circuit and supplied by said alternating currentsource, polyphase windings connected to the corresponding phase windingsof the several rotary' converters and connected in parallel to thealternating current source, said polyphase windings being inductivelyrelated to each other to produce equal and opposite inductive effectsduring the normal operation of the rotary converters.

. 2. In combination, an alternating current circuit, a direct currentcircuit, two rotary converters connected in parallel between said twocircuits, said rotary converters being directly connected to said directcurrent circuit, and windings in corresponding leads of the connectionsbetween the two rotary' converters and the alternating current cir, cuitand in opposing inductive relation for the flow of current between theconverters and such circuit. l

3. In combination, analternating current r circuit, a direct currentcircuit, two rotary converters connected in parallel between said twocircuits, a single core, and windings comprising sets of coils on saidcore and connected in corresponding leads of the connections from thetwo converters respectively to the alternating current circuit, thewindings connected with the two converters being wound on the core sothat the effects produced by the fiow of current between the twoconverters respectively and-the alter-v nating current circuit tend toneutralize' -windings connected to each other and connectedArespectively in the leads from` the two converters to the alternatingcurrent circuit and arranged to oppose each other for the l'low ofcurrent between such circuit and the two converters.

5. In combination, an alternating current circuit, a direct currentcircuit, a plurality of rotary converters connected in parallel betweensaid two circuits, said rotary converters being connected directly tosaid direct current circuit, a plurality of windings connected betweenthe several rotary converters rf pectively and the alternating currentcircuit and arranged in inductive relation to one another so that theyreact among themselves to offer small impedance to the flow of currentbetween the converters and the alternating current circuit and largeimpedance to the flow of current from converter to converter.

6. In combination, an alternating current circuit, two rotary convertersconnected to said alternating current circuit, windings through whichsuch connections are made respectively, the windings associated with thetwo converters being in inductive relation to each other so that theyeach tend to nentralize each other for the flow of current between theAalternating -current circuit and the converters, and a direct currentcircuit to which the direct current ends of the converters are connectedin parallel.\

47. In combination, a polyphase alternating current circuit, a directcurrent circuit, two rotary converters arranged in parallel between saidtwo circuits, and a pair of static transformer windings for each phaseof the polyphase circ'iu't, the two windings of each pair beingconnected to each other and in opposed inductive relation to each otherand located in correspondingleads between the two convertersrespectively and the alternating current circuit.

8. In combination, a source of polyphase alternating current, a directcurrentl circuit, a plurality of rotary converters connected in parallelto said direct current circuitf'and supplied by said alternating currentsource, a polyphase transformer between said source and said rotaryconverters,corresponding phase windings of the several rotary-convertersbeing connected in parallel through transformer windings disposed aboutthe same magnetic path, said transformer windings being inductivelyrelated to each other to produce a condition of neutral magnetization insaid magnetic path during normal windings connected to the armaturewindv ings of said dynamo electric machines and connected in parallel tothe alternating currentv circuit, said lirst .windings being inductivelyrelated to each other to produce equal and opposite inductive effectsduring the normal operation of said dynamo electric machines.

10..In combination, an alternating cur- 1 rent circuit, aplurality oftranslating de-` evices connected to said circuit, a plurality oftransformer wlndings disposed on a common z Copies of this patent mayloe obtained for core and connected in parallel between said' circuitand corresponding windings on said translating devices, a separateelectrical connection between said corresponding windings ofsaid'translating devices, said transformer windings being soproportioned and .inductively relatedlto eachother as-to produce aneutral magnetic effect in said core during the normal operation of saidtranslating devices, and being so connected that the electrical paththerethrough from one translating device to another is through both ofvsaid transformer windings in series.

Milwaukee\Vis., May 10, 1910.

A'In testimony whereof we aflix our signa tures, in the presence of twowitnesses.

LOUIS E. BOGEN.

LOUIS O. NICHOLS.

Witnesses: l

Gro. B. SCHLEY, OHAs. L. BYRON.

five cents each, by addressing the "Commissioner of latents,

Washington, D. C.

